In the United States alone, twenty-five million persons suffer from peptic ulcers, four million of them chronically. Approximately one million victims are hospitalized annually. The major etiologic agent of gastritis and peptic ulcers is Helicobacter pylori (H. pylori).
While several methods to detect H. pylori infection are known, all suffer from one or more drawbacks. Serological detection of antibodies against H. pylori is routinely employed. Unfortunately, the antibody continues to be present even after eradication of the organism. A breath test, involving the consumption of radioactive carbon has been approved, but only detects the presence of the organism. Endoscopy followed by biopsy is another method to detect and to some extent localize Helicobacter, but this is a serious invasive procedure. A non-invasive method to localize H. pylori within the stomach and duodenum does not exist. The ability to localize H. pylori within the upper gastrointestinal tract would be an important component of the clinician's treatment protocol, enables, for example, non-invasive observation of the course of therapy.